In my prior U.S. Pat. No. 4,496,464, there is disclosed a filter system that has a filter media comprised of particles of filter material contained within a vessel. Liquid flows through the vessel and the filter media in a particular manner in order for the filter media to remove unwanted contaminants from liquid. The present invention is an improvement over the filter apparatus set forth in my previous U.S. Pat. No. 4,496,464. Reference is made to the prior art cited in that previous patent.
In my copending U.S. patent application Ser. No. 07/001,912 filed Jan. 9, 1987, now U.S. Pat. No. 4,787,987 there is disclosed a filter vessel within which a filter media is supported. The media includes pecan hulls, or a mixture of pecan hulls, walnut hulls, and apricot pits. The present invention sets forth in greater detail the use of pecan hulls; as well as a mixture of pecan hulls and walnut hulls; pecan hulls and apricot pits; and, pecan hulls together with varying amounts of apricot pits and walnut hulls.
Walnut hulls have been used for many years as a filter media, as evidenced by the Hirs, U.S. Pat. Nos. 3,992,291; 3,780,861 and to Clark, U.S. Pat. No. 2,733,138. In the present invention, the term "walnut hulls" is intended to include the type of hulls or shells that one would expect to be shipped to him should he order walnut hulls from a commercial firm that specializes in the sales of filter media. There are those who allege that black walnut hulls are superior to other walnut hulls and such use is included by the term "walnut hulls". Applicant prefers to use pecan hulls admixed with ordinary walnut hulls and sometimes, apricot pits, as his filter media.
The present invention also sets forth an improved filter system wherein the filter media is scrubbed and cleaned within the vessel, thereby cleaning the media from time to time without removing the media from the vessel.